ISLAMABAD, Pakistan -- A powerful earthquake triggered landslides, flattened entire villages of mud-brick homes, and toppled an apartment building yesterday, and a Pakistani official said at least 18,000 people were believed killed as it devastated a mountainous swath touching Pakistan, India, and Afghanistan.
The casualty toll from the 7.6-magnitude tremor rose sharply early today as rescuers struggled to dig people from the wreckage, their work made more difficult as rain and hail turned dirt and debris into sticky muck.
Major General Shaukat Sultan, Pakistan's chief army spokesman, told Pakistan's Geo TV network that more than 18,000 had been killed -- 17,000 of them in Pakistani Kashmir, where the quake was centered. Some 41,000 people were injured, he said.
For hours, aftershocks rattled an area stretching from Afghanistan across northern Pakistan into India's portion of the disputed Himalayan region of Kashmir. Hospitals moved quake victims onto lawns, fearing tremors could cause more damage.
The earthquake, which struck just before 9 a.m. yesterday, caused buildings to sway for about a minute in the capitals of Afghanistan, Pakistan, and India, an area some 625 miles across. Panicked people ran from homes and offices, and communications were cut to many areas.
Most of the devastation occurred in the mountains of northern Pakistan, where the dead included 250 girls crushed at a school and 200 soldiers on duty in the Himalayas.
The US Geological Survey said the quake was centered about 60 miles northeast of the capital, Islamabad, in the forested mountains of Pakistani Kashmir.
''It is a national tragedy," Sultan said earlier. ''This is the worst earthquake in recent times."
In Mansehra, a shopowner named Haji Fazal Ilahi stood vigil over the body of his 14-year-old daughter, which lay under a sheet on a hospital mattress. He said his wife, another daughter, and a brother also died when the family's house fell.
''I could see rocks and homes tumbling down the mountains," said Ilahi, who was driving to his village of Garlat when the quake struck. ''When I reached my village, there was nothing left of my home."
India's government offered condolences and assistance to Pakistan, a longtime rival with which it has been pursuing peace efforts after fighting three wars since independence from British rule in 1947, two of them over Kashmir.
''While parts of India have also suffered from this unexpected natural disaster, we are prepared to extend any assistance with rescue and relief which you may deem appropriate," Indian Prime Minister Manmohan Singh said in a message to Pakistan's president, General Pervez Musharraf.
India reported at least 340 people killed and 800 injured when the quake collapsed 2,700 houses and other buildings in Jammu-Kashmir state. Most of the deaths occurred in the border towns of Uri, Tangdar, and Punch and in the city of Srinagar, said B.B. Vyas, the state's divisional commissioner.
Telephone lines were down. Some bridges developed cracks, but traffic was reported to be passing over them.
A senior Pakistani army officer said 200 soldiers were killed by debris and landslides in Pakistan's portion of Kashmir.
He spoke on condition of anonymity because he was not authorized to speak to journalists.
About 1,000 civilians died in that region, said Sardar Mohammed Anwar, the top government official in the area.
''This is my conservative guess, and the death toll could be much higher," Anwar told Pakistan's Aaj television station, adding that most homes in Muzaffarabad, the area's capital, were damaged, and schools and hospitals collapsed.
The death toll was at least 1,600 in Pakistan's North West Frontier Province, said Akram Durani, the province's top elected official.
Ataullah Khan Wazir, police chief in the northwestern district of Mansehra, said authorities there pulled the bodies of 250 students from the wreckage of one girls' school in the village of Ghari Habibibullah. About 500 students were injured, he said.
Dozens of children were feared killed in other schools.
Mansehra, about 90 miles northwest of the capital, was believed to be a hotbed of Islamic militant activity during the time the Taliban religious militia ruled neighboring Afghanistan.
Al Qaeda operatives trained suicide squads at a camp there, Afghan and Pakistani sources told The Associated Press in 2002.
Afghanistan appeared to suffer the least damage. In its east, an 11-year-old girl was crushed to death when a wall in her home collapsed, police official Gafar Khan said.
A US military spokesman, Army Lieutenant Colonel Jerry O'Hara, said the quake was felt at Bagram, the main American base in Afghanistan, but he had no reports of damage at bases around the country.
The United Nations sent an emergency coordination team to Pakistan immediately to begin relief efforts.
The eight-member team from the UN Office for the Coordination of Humanitarian Affairs was due in Islamabad today to help set up a center for coordinating the global body's emergency response.
''We know that every hour counts in an earthquake of this magnitude and the United Nations is ready to assist the country affected in any possible manner," Jan Egeland, undersecretary-general for the relief group, said yesterday in a statement from UN headquarters.
The UN International Children's Emergency Fund (UNICEF) said it had begun moving blankets, clothing, tents, emergency medical supplies, food for infants and water purification tablets from a Karachi warehouse to quake affected areas.
UNICEF executive director Ann Veneman said children made up half the population of the affected areas and would be vulnerable to hunger, cold, illness and trauma.
In Geneva, UN humanitarian affairs spokeswoman Elisabeth Byrs said, ''These are our top coordination officials. At least two of the staff we sent have experience from dealing with the [Indian Ocean] tsunami."
The International Red Cross said it also was preparing an emergency response. Earlier yesterday, two local Pakistan Red Crescent groups were deployed to Pakistan's northwest frontier and another one to Kashmir to assess the damage, said Marie-Francoise Borel, spokeswoman for the International Federation of Red Cross and Red Crescent Societies.
Material from Reuters and The